How to place match the floor of a picture with a plane using f-spy?
Incorrect perspective reconstruction
Your reconstructed camera in the blendfile has different orientation from the one used in the source image. Just look at the angle between the floor ad the camera's horizon: yours is totally parallel.
The narrow focal lenght of the camera is not helping either in hiding the little differences.
Here's my reconstruction in fSpy:

And here the reconstruction of the scene.